Project Summary: The long-term goal of this research is to understand how the mammalian auditory cortex processes and learns social communication sounds. A mouse model is proposed for investigating this in a natural communication context between mouse pups and adult female mice. We used advanced quantitative methods to evaluate what information neurons in the auditory cortex can provide about these sounds that will facilitate their detection, discrimination and categorization. Three specific aims are proposed. First, we will test the hypothesis that animals for whom the sounds are communicative represent the sounds differently from those for whom the sounds are not communicative. Second, we will look at what neural response properties help to improve a neuron's ability to provide information about these communication sounds. Third, we investigate the spatial organization of the auditory cortex for processing these sounds. Researching these questions in a mouse model provides the future opportunity to use genetic methods to dissect the mechanisms involved in communication sound processing. Relevance: This study will improve our understanding of how the brain detects, discriminates and categorizes communication sounds. These tasks are fundamental to how humans perceive and process speech. Thus, this research may eventually help us determine how normal neural processing breaks down in individuals with speech hearing problems.